Hydraulic electric bell hoist



May 27, 1930.` G. Fox 1,760,637

,HYDRAULIC ELECTRIC BELL HOIST y, Filed June 2, 1927 2 Sheets-Sheet l 1 @i @i j 1 2 l S P Y* l 1 E HYDRAULIC ELECTRIC BELL HOIS'I Filed June 2, 1927 2 Sheets-Sheet 2 PatemgaMay 27, 1930 UNITED STATES PATENT OFFICE GORDON FOX, 0F CHICAGO, ILLINOIS, ASSIGNOR '10 FREYN ENGINEERING COMPANY, .0F CHICAGO, ILLINOIS, A CORPORATION 0F MAINE HYDRAULIC ELECTRIC BELL HoIs'r Application led June 2, 1927. Serial No. 195,882.

The present invention relates to hydraulic electric bell hoists.

More particularly the present invention relates to structure `suitable for operating the loadingbells of blast furnaces. In order to cut down the labor in loading blast furnaces it is highly desirable to control the operation of a blast furnace bell automatically,

- wherebyv upon the movement of a simple VVswitch, valve or the like, a cycle is inaugurated and carried through, resulting in the desired operation of the blast furnace bell. This cycle may be inaugurated in response to the operation of the skip hoist or other device for loading the bell. In a blast furnace plant, the skip hoist, involving the distributor and the bells, may be interlocked, so VVthat it is necessary for the scale car operator only to start the skip hoist in order to bring about a complete cycle of operation comprising the movements of the skip hoist,ldistributor and bells. y An object of the present invention isto provide a bell hoist which involves relatively simple parts, Which is positive in operation, which requires a minimum of space, Which provides the-necessary speed control and which will cut down to a minimum the amount of attention required of an operator. A further object is to provide a bell hoist involving a combination of hydraulic and electrical mechanisms Which is Well adapted to meet the needs of commercial operation.

A further object is to provide a system involving separate operating mechanisms for the two bells of a double bell blast furnace, either of which operating mechanisms may be conveniently used for operating either of said bells.

Further objects Will appear as the descripf tion proceeds.

Figure 2.

open by gravity. It is a further function of the hydraulic cylinder as contemplated in this invention to provide a retarding motion during the lowering of the counterweight, Whereby to governthe speed of the closure of the corresponding bell. In connection Withl each hydraulic cylinder, it is proposed to use a rotary' hydraulic pump, of Which there are several types available in commercial use. The particular types of hydraulic pumps contemplated are such that they can be used interchangeably for pumping fluid under pressure -cr as hydraulic motors to convert hydraulic pressure to rotary motion. The pump referred to is connected to a dynamoelectric machine, which operates as a motor or -as a generator, depending upon Whether 'said dynamo-electric machine is called upon to perform motor or generator functions. Not only doesl the hydraulic system function to translate straight line movement to rotary movement, and conversely, but it also functions to translate from high speed motion of the motor With a small torque to a low speed motion of the hydraulic cylinder With large force, or, conversely, from a low speed motion of the hydraulic cylinder 'with a large force to a relatively high speed motion of the motor with generator functions. In this action the present invention contemplates the replacement of gear reducing means or arrangements of cables and sheaves. If the cable pull of the` bell hoist is applied directly to any form of Winch mechanism, said mechanism must-be heavy enough in construction to handle thel large forces corresponding to the cable pull. If, on .the other hand, it is desired to construct a small Winch or other mechanism to handle the bells or counterweights, it is necessary to interpose a considerable number vof sheaves and cables in order to translate the large force with sloWv motion of the bell cables to the smaller force with faster motion at the Winch.

The cycle of operation of the hoisting mechanism for each bell may be substantially the same as described in applicants cepending application Serial No. 97 ,811, filed March 26, 1926, entitled Electric hoists. According to the present invention, in order to open the bell the electric Inotor is started, driving a hydraulic pump and causing a flow of fluid into a cylinder and raising a counterweight and allowing the bell to open. When the bell has opened a desired Iamount, the motor can be made. by means such as described in said application and which will be describedhereinafter, to slow down and substantially stop, as for example by introducing suitable resistors in series and in shunt with the motor. After a desired period, or upon the happening of a certain event, the electrical circuits can be changed to allow the counterweight to lower. In so doing, the counterweight will force fluid out of the cylinder and through the rotary pump into a storage reservoir. In so doing, the pump will drive the motor in the reverse direction as a generator. By the provision of suitable braking circuits, which braking circuits will be referred to hereinafter, the retarding eect of the motor may be regulated to thereby govern the speed at which the counterweight is lowered. Moreover, the present invention contemplates means whereby the cycle may be interrupted as desired and the bell and counterweight may be held in an intermediate position or an open position.

Referring to the drawings, the letter A represents one bell and the letter B indicates a second and larger bell, which cooperate with one another in the loading of the blast furnace C. The two bells A and B may be arranged concentrically ina manner which is common in practice, the bell A being controlled by a cable D, while the larger bell B is controlled by the cable E, levers F' and G being connected to said cab-les D and E, 1espectively, said levers F and G being connected to the bells A and B,'respectively. The cable D is connected tthe hydraulic cylinder H, which is adapted to have a reciprocating movement along a vertical axis, the inner wallvof saidcylinder H having fluidtight sliding engagement with the fluid supply member I, the interior of which is connected by means of the pipe J to rotary fluid pumps andliquid reservoirs, to be referred toy hereinafter, the pipe J being provided with the valve J1. The cable E is connected to the cylinder K, which is adapted tohave a reciprocating movement along a vertical axis, the inner wall ofsaid cylinder K having sliding fluid-tight engagement with thefluid supply member L, the interior of which isl connected bymeans of the pipe M to the two rotary pumps and fluid reservoirs above referred to, thepipe M being yprovided with the valve M1. Each of'thecylinders H and K is provided with a counterweight N, which may be `chosen of a size suitable for the bell with which it cooperates.

As noted from Figure 1 of the drawing, the pipes J and M are connected to the common pipe O, which common pipe is connected to the corresponding sides of the rotary pumps Pand Q through the pipes P1 and Q1. The pipe O is provided with the valve O1 between the pipes J and M. The other sides of said rotary pumps P and Q are connected to the oil reservoirs It and S through the pipes P2 and Q2. Pipes-P1 and Q1 are provided with the valves P3 and Q3, respectively. The pipes P1 and Q1 are also connected to the upper regions of the reservoirs R and S through the relief pipes R1 and S1, respectively, which relief pipes R1 and S1 are provided with the relief valves R2 and S2. Connected to drive the rotary pump P is the dynamo-electric machine T, and similarly connected to drive the rotary pump Q is the dynamo-electric machine U. The control panels foi' the dynamo-electric machines T and U, respectively, are indicated by the characters T1 and U1. Con nected to the control panel T1 are the stall limit switch T2 and the slow-down limit switch T3. Said stall limit switch T2 is adapted to be closed by a portion of the cylinder H, or a member which moves with said cylinder H when said cylinder H is at or near the upper limit of its travel, and the slowdown limit switch T3 is similarly adapted to be opened when said cylinder H is a short distance above the lower limit of its travel. Abutments H1 carried by said cylinder H are illustrated, for controlling the switches T2 and T3. Similarly connected to the control panel U1 are the stall limit switch U2 and the slow-down limit switch U3 which are adapted to be selectively oper ated by the cylinder K when said cylinder is at predetermined places in its range of travel. Abutments K1-K1 carried by the cylinder K are illustrated, for controlling the switches U2 and U3. Panel T1 is connected to switch T2 by means of the twowire cable T1 and to switch T3 by the two-wire cable T5. Similarly, panel U1 is connected to switch U2 and to switch U3 by means of the two-wire cables U4 and U5, respectively. Panels T1 and U1 are connected to the dynamo-electric machines T and U by the four-wire cables T and U, respectively. Each of the cables T4 and U4 is provided with a switch X.'

An electric control system for each ofthe dynamo-,electric machines is illustrated in Figure 2. said system being part of the subject matter of another appli'cation'iled by the present applicant and is therefore not being claimed herein. Said other application bears Serial No. 97,811, and was filed March 26, 1926.

The armature of either dynamo-electric machine T' or U is indicated in Figure 3 by the numeral 15, and the series field winding and the shunt field winding of said dynamoelectric machine are indicated by the numerals 16 and 17, respectively. Thenumerals 18-18 indicate the two leads of an electric circuit which may be controlled by the blades 19-19 of a double/pole switch.

Connected across the leads 18-18 is a. circuit including contactor 20, the armature 15,

the series field winding 16, the sections 21, 22

and 23 of an accelerating resistance, and the contactor 24. Also connected in the circuit referred to is the overload relay coil 25. The sections 21, 22 and 23 of the accelerating resistance are adapted to be shunted out of circuit for which purpose accelerating contac-I tors 27,28 and 29 are provided. Connected in parallel across the circuit of the armature 15, series field winding 16 and section 21 of the accelerating resistance is ashunting circuit controlled by the normally closed contactor 30. The normally closed spring contactor 31 is provided for connecting the braking resistors 32 across the circuit including armature 15, series field winding 16 and sections 21 and 22 of the accelerating resistance.

Connected across the leads 18-18 is a circuit including-the normally closed' time delay relay 33, the operating coils 34 and 35 (which coils are in parallel with each other) and the normally open start button'l37. The normally closed overload relays 38-38 may be provided in the circuit immediately above described, which overload relays 38-38are responsive to energization of the overload relay coil 25,. Connected in parallel relationship with the time delay relay 33 and the coils 34 and 35 is the operating coil 39 for contactor 30. Operation of the start button 37 connects said operating coil 39 across the leads 18-18. Arranged in parallel relationship with the start button 37 isA the slow-down limit switch T3, which is biased to closed position.' Connected in parallel relationship with the start button 37 and the slow-down limit switch T3 is the auxiliary contact 41, which moves in unison with contactor 20. Said auxiliary contactor 41 is in closed position when contactor 2O is in closed position.

Mounted in parallel relationship with the operating coil 39 for vthe contactor 30 is a circuit including the stalling limit switch T2, the operating coil 43 for the contactor 31,

and an auxiliary contact 44, which is mounted to move in unison with contactor 20. Said auxiliary contact 44 1s in closed circuit position when contactor is in closed position. Connected across the operating coil 43 is the operating coil 45 for the accelerating relay contacts 46, 47 and 48, which control the relay coils 46a, 47 a and 48, respectively, which coils in turn control contactors 27, 28 and 29, respectively. i

Also connected 1n parallel circuit across the operating coil 39 for the contactor 30 is the operating coil 49 for the time delay relay 33 and the auxiliary Contact 50, which moves in unison with the contactor 31. Said auxiliary contact 50 is closed when contactor 31 is closed.

Figure 3 indicates the connections of the slow-down limit switch and the stall limit switch with the panel T1 and the connections of t-he dynamo-electric machine T with said panel. It will be understood, of course, that the connections of the panel U1 with its corresponding slow-down limit switch and stall limit switch and with its corresponding dynamo-electric machine U will be similar to those shown in Figure 3. In Figure 1 the numeral 51 indicates a connection between the panels U1 and T1 by means of which either panel may be used with either of the dynamoelectric machines. This connection forms no part of the present invention and need not be described herein.

The bells A and B are normally held in sealed position by the pull of the cylinders H and K, respectively, which cylinders act as counterweights. In charging the furnace C it is necessary to communicate lifting movements to said cylinders H and K. Inasmuch as the operations of said cylinders are normally independentof one another. a description of they control of one of said cylinders will suiiice for a description of the control for the other of said cylinders. Referring foi` example to the cylinder H, which controls the upper bell A, it is necessary, in order to raise same, to set the corresponding dynamoelectric machine T in operation as a motor. Operation of the dynamo-electric machine T as, a motor drives the pump P, causing a flow of oil or other fluid from the reservoir R through said pump P and pipe line .I to the iiuid supply member I. Flow of oil through the member I to the cylinder H results in the lifting of the cylinder H, allowing the bell A- with its burden to open. Whenvthe bell has opened a desired amount, the

mot-or can be made to slow down and substantially stop by introducing suitable resistors in series and in shunt with the motor. After a desired period, as determined by a time relay, or upon the happening of a certain event, the electrical circuits can be changed in a manner 'whereby the counterweight comprising the cylinder H will be lowered. Lowering of the cylinder H will force the oil out of said cylinder H through the reversible pump P into the reservoir R. In this operation the pump will drive the motor in a reverse direction as a generator. Suit-able braking circuits will be placed around the motor armature to gov ern the retarding eect of the motor and thereby govern the speed at which the cylinder H is lowered. Not only does the flow of oil communicate rotary motion of the motor to a linear motion of the cylinder, or, conversely, not only does it translate a linear motion of the cylinder to a rotary motion of the motor, but the flow of oil translates from a high speed motion of the motor with small torque to a low speed motion of the cylinder with a large force; or, conversely, it translates a low speed motion of the cylinder to a high speed motion of the motor. By reason of this function it is possible to eliminate gear reduction means and arrangements of cables and sheaves. This may be explained by the statement that if the cable pull of the bell hoist is applied directly to any form of Winch or similar mechanism, that mechanism must be heavy enough in construction to handle large forces corresponding to the cable pull. If, on the other hand, it is desired to construct a small winch or other mechanism to handle the bells or counter- Weight, it is then necessary to interpose a considerable number of sheaves and cables in order to translate the large forces with slow motion of the bell cables to a smaller force with faster motion at the winch.

The electrical control will now be briefly referred to, said electrical control being unclaimed in this application inasmuch as it forms part of the subject matter of the copending application above identified filed by the present applicant. In order to set the dynamo-electricmachine T in operation to drive the pump P to force oil or other liquidinto the cylinder H, the start button 37 is depressed momentarily. This closes the circuit from the positive lead 18 throughl the operating coils 34 and 35 of contactors 2O and 24, respectively, and through the time delay relays 334-33 to the negative lead 18. By reason of the energization of the coils 34 l and 35, the contactors 20 and 24 are closed,

connecting the dynamo-electric machine T across the leads 18-18 as a motor, having the sections 2l, 22 and 23 of the accelerating resistance in series with the armature and series field y,of said motor. Theclosing of contacter 2O results in the closing of-the auxiliary contact 41, which auxiliary contact isin parallel relationship with the start button 37. Said auxiliary contact 41 therefore provides a maintaining circuit after the operator has released the start buttonA 37. At this time the circuit of the. controlling coil 39 of contacter 30 is energized, causing said contactor 3() to open. Circuit is also completed at this time from the positive lead 18 through the stalling limit switch T2, through the operating coil 43 of contacter 31, through the auxiliary contact 44 and'auxiliary contact- 41, to the negative lead 18; The energization of the operating coil 43 causes the opening of contactor 31. At this time the stalling limit switch T2 is closed and the slow-down limit switch T3 is open. As a lresult of the actions recited above, the dynamo-electric machine T is energized as a motor to drive the pump l?. At this time the sections 21, 22 and 23 of the accelerating resistance are in series with the armature 15, and the armature shunting circuits controlled by the contactors 30 and 31 are open. Simultaneously with the above actions, a circuit is completed through the accelerating relay 45, which results in the successive encrgization of the coils 46, 47a and 48, which coils control the accelerating contactors 27, 28 and 29, respectively. Said accelerating relay 45 willbe chosen of the time element type, which is well known to those skilled in the art. The successive energizations of the operating coils 46a, 47a and 48a will cause the successive closing of said accelerating contactors 27, 28 and 29, whereby the dynamoelectric machine T will be connected across the leads 18-18 with ,no sections of accelerating resistance in circuit. The dynamoelectric machine T proceeds to drive the pump P to deliver Huid to the cylinder H to raise same, and the bell A opens by gravity.

When the cylinder H has traveled a short distance, the slow-down limit switch T3 will be moved to closed position; any preferred means responsive to movement of said counterweight being suitable for operating said switch T3. There is no immediate effect yfrom this closure. When the bell A reaches afsubstantially full open position, the stalling limit switch T2 will be opened. Opening of said stalling limit switch T2 results in the deenergization of the operating coil 43 of contaetor 31, causing said contactor 31 to close. Closure of contacter 31 results in the Vclosure of the auxiliary contactor 50, resulting in the energization of the time delay, relay coil 49, which coil 49 controls the time delay relay 33. Opening of said stalling limit switch T2 also results in the deenergization of the operating coils 46a, 47a and 48, whereby the accelerating contactors 27, 28 and 29 are caused to open. At this time the dynamo-electric machine T` is connected across the line With all of the sections 21, 22 and 23 of the accelerating resistance in circuit and with the braking resistors 32 shunted across said dynamo-electric machine and sections 21 and 22 of the accelerating resistance. The values of these resistors can be so adjusted that the dynamoelectricl machine will practically stall, developlng only suflicienttorque to hold up the cylinder H. If there should be any `Inovement, the speed of travel would be exceedingly slow. At this time the burden is being permitted to drop from the bell into the blast furnace. Attention is -directed at this point to the relief valve R2, which permits the dynamo-electric machine T and the pump Pto operate in a pumping sense to maintaln a pressure to hold up the cylinder H and to hold the bell Ain open position. It may be desired to utilize the functions of the relief valve R2 rather than to cause the stalling of the dynamo-electric machine T to give a time delay for dumping. Moreover, the relief va'lve permits holding the bell open for inspection or cleaning.

After the lapse of a predetermined time, the time delay relay coil 49 will result in the opening of the time delay relay 33, resulting in the deenergization of the coil 34 of contactor 20 and the coil 35 of the contactor 24. The dynamo-electric machine T is now disconnected from the mains, and the weight of the cylinder H will cause the backflow of fluid through the pipe J, pipe P1 and pump P to thev reservoir R. Reverse operation of the pump P will cause the dynamo-electric machine T to operate as a generator with a dynamic braking circuit across the armature and series field, which dynamic braking circuit includes the resistors 21, 22 and 32. The corresponding bell A will close as the cylinder H descends. When near the lowermost position of the cylinder H, the slowdown limit switch T3 will be opened, which open-circuits the coil 39 of the contacter 30, resulting in the closing of said contactor 30, applying a lower resistance dynamic braking circuit across the armature and series field lwinding of the dynamo-electric machine,

has the advantage that it allows interlocking is provided with a brake, the bells are biased to, c-lose; yet they can be held open if desired. This latter function is accomplished by means of the switch Xin each ofthe stalling v limit switch circuits, whereby the corresponding stalling limit switch T2 or U2 may be rendered inoperative. The corresponding relief valve R2 or S2 then permits short-circuiting of the oil or other liquid through the corresponding pump and reservoir, maintaining a ypressure sucient to hold up the corresponding cylinder H or K. When the switch X in either the line T4 or U4 is again closed, the cycle is continued and completed; that is, after the time relay functions, the

corresponding cylinder drops, retarded by the pump and the motor, which motor operates as a generator.

The device requires a minimum of floor space, because of the vertical position of the cylinders H and K, and will permit the location of the combination motor pump unit at any point near these cylinders, but without requiring any particular mechanical space relationship. The present invention renders easy a fea-ture which is not attributable to any other electric bell hoist, insofar as applicant is informed, in that the unit comprising a motor pump and its control can be applied either to the large bell or the small bell of a furnace. The operating means for the two bells may be duplicates throughout, the only difference being that the large hell will operate with a higher oil pressure and a heavier counterweight. The simple arrangement of the interconnected piping with valves will allow either pump unit to function in connection with either cylinder, so that repairs can be made upon one unit while the other functions to handle both the large and the small bclls. If the pump Q is out of commission, valve Q3 is closed and valve O1 is opened. In order that the pump unit P may operate on the cylinder K, valve J1 is closed and valve M1 is opened. To control cylinder H from the pump unit P, it is necessary to close valve M1 and open valve J1. When pump unit P is out of commission, valve P3 is closed and valve O1 is opened. To control the cylinder H from pump unit Q, valve M1 is closed and valve J1 is opened. To control cylinder K from the pump Q, valve J1 is closed and valve M1 is opened.

By the arrangement :of interconnected piping, the advantage vis had that either pump unit may function in connection with either cylinder, so that repairs can be made upon one unit while the other functions to handle both the large and the small bells. Moreover, the equipment can be constructed at a cost lower than other comparable types of bell hoist.

Though a preferred embodiment of the present invention has been described in detail, many modifications will occur to those skilled in the art. It is intended to cover all such modifications that fall within the scope of the appended claims.

What is. claimed is- 1. In combination, a member the movement of which is to be controlled, a counterweight for biasing same to 'a raised position, hy-

2. In combination, a member the Inovement o f which is to be controlled, a counterweight folbasing same toa raised position,

hydraulic means for lifting said counterweight to permit said member to descend, a reversible pump forI pumping liquid to said hydraulic means and to receive power from said hydraulicmea'ns, and a dynamo-(electric machine mechanically connected to said reversible pump, said dynamo-electric machine being provided with a braking electric circuit operative to perform braking functions when said dynamo-electric machineiis being driven as a motor.

3. In combination, a member the move-` ment of which is to be controlled, a counterweight for biasing same to a raised position, hydraulic means for lifting said counterweight to permit said member to descend, said hydraulic means including a reversible pump, a reservoir for fluid, and by-pass means between said reservoir and pump whereby the pressure upon said hydraulic means may be maintainedat a desired figure without stopping said pump.

. 4. In combination, a member the movement of which is to be controlled, hydraulic cylinder means for biasing same to a raised position, a. pump for delivering fluid to said cylinder means to permit said member to descend, said pump being reversible, and a dynamo-electric machine electrically connected to said pump wherebyto receive energy from said pump for braking purposes.

5. In combination, a member the movement of which is to be controlled, hydraulic cylinder means for biasing same to a raised position,a pump for delivering fluid to said cylinder means to permit said member to descend, said pump being reversible, and a i' dynamo-electric machine electrically connected to said pump whereby to receive energy from said pump for braking purposes, said' cylinder means being vertically disposed whereby to occupy a minimum of floor space.

6. In combination, a member the movement of which is to be controlled, counterweighted cylinder means for biasing same to a raised position, a pump connected with said counterweighted cylinder means for -delivering fluid thereto to lift said counterweighted cylinder means to permit said member to descend, a pump for delivering fluid tp said cylinder means and for receiving energy from said cylinder means when said cylinder means descends, a dynamo-electric machine connected to saidpump, and limit switches adapted to be operated in response to movement of said cylinder means for controlling said dynamo-electric machine.

Signed at Chicago, Illinois, this 24th ,day

of ivy, 1927.

-GoRDoN Fox. 

